Karl august ekman



UNITED STATES PATENT OFFICE.

KARL AUGUST EKMAN, OF BOFORS, SVEDEN,

ROTARY ENGINE.

SPECIFICATION forming part of Letters Patent No. 342,079, dated May 18,1886.

Application filed April B, 1886. Serial No. 193,170. (No nicdel.)Patented in Sweden January 2li, ISBG, No. 25T.

l head provided with inlet and out-let ports and with an exhaust.

The invention also consists of various parts and details andcombinations of the same, as will be fully described hereinafter, andthen pointed out in the claims. I

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar letters of reference `indicatecorresponding parts in all the figures.

Figure l is a sectional elevation'of my improvenient on the line u z,Fig. 2. Fig. 2 is a longitudinal cross-section of the same on the linefr 0 y, Fig. l. Fig.3 is a detail face view of the disk-valve. Fig. 4'is a sectional face view ofthe fixed cylinder-head on the line w w,Fig. 2. Figs. 5, 6, and 7 reprcsentinodili` cations hereinafter morefully described.

The engine cylinder or casing A is provided with a baseplate on whichthe engine rests, and with an elliptical groove or recess, a, and

, a central hub, forming a bearing for the shaft E, on which is secureda cylinder-head, C, by means of a key, G. The cylinder-head B is rigidlyattached by the bolts P to the cylinder or casing A, and is providedwith a circular recess',r, from which radiate the exhaust-channels q,'and which recess has the radial inletports p. The exhaust-pipe S leadscentrally to the recess r.

The movable cylinder-head C covers the elliptical recess or groove a inthe cylinder A,

and is provided with the annular'offset or projection D, which has twoor more transverse recesses in which are mounted the pistons K, eachpiston, being attached to an arm which is Y 5o .fnlcrumed on the bolt orshaftfe, secured in the annular projection D of the cylinder-head C.

The pistons K are eachmade in two parts, which fit tightly in theelliptical recess or groove e, and are held in close contact with thesame by small spiral springs pressing the two parts of the pistonoutward. Against the circular surfaces of the pistons K press the padsn, placed in grooves formed in the annular projection D, and held incontact with the pistons K by' spiral springs.

The annular projection D touches the cylinder or casing A in four ormore places, and the cylinder A is provided at each of these contactplaces with a recess, in which is placed a packingstrip, m, pressedoutward into contact with the annular projection D by a spiral spring.

On the inner end of lthe shaft E is secured a disk-valve, F, placed inthe steam-chest d, formed between the cylinder A and the cylinder-headB. The steam -inlet-pipe R opens `into the steanrchest d, and thedisk-valve F is provided with two ports, l.

The operation is as follows: The steam enters through the steam inlet-pipe R into the steamchcst d, and its pressure forces the diskvalve F toseat itself against the inner faceof the ied cylinder-head'B. The portsZof the disk-valve F connect alternately with the radial inlet-ports p,thereby admitting steam into the elliptical groove or recess a of thecylerts its pressure against the pistons K, which are pushed forward inthe direction of the arrow a', and cause the cylinder-head C, the shaftE, and its valve-disk F to rotate. As the pistons ,K are fulcrumed atethey swing so as to conform to the shape of the elliptical groove a, inwhich they travel. As soon as the pistons K, have passed the outletportsq the steam behind the 'pistons enters the outlets ports q and therecess r, from which it escapes into the exhaust-pipe S. The 'pistons Kreceive a secondary impulse from the steamas soon as they have passedthe next inlet-port, p, the valve-disk F establishing the necessary IOO'c' and the. port p. As the outletLports q are s d i. 342,079v

communication between the el'lipticalfgroove alwaysfopen, the steam canescape freely.'

The cylinder-head C and the valve-disk F may be conical in shape, asindicated by the dotted lines o t and o t', the contact-surfaces of thecylinderAand the head B being shaped correspondingly. The eccentricityof the elu liptical groove a and the number of pistons K.

may be varied from the simple elongated recess a, with two pistons, asshown lin Figs. 1 and 2, to the form where the'annular projection D issupported at three or six places, as

shown in Fig. "5, with three pistons, or to the form where the annularprojection has four contact-places, as shown in Fig. 6,'with fourpistons. v

Instead of h aving the pistons K pivoted on pins e, they may beconstructed ofl two parts, as shown in Fig. 7, of which one 'parttelescopes .the other, and the two parts are pressed out! ward from eachother by a spiral spring.V In case thc latter -form of piston is used,the engine may be reversed by making the now fixed cylinder-head Bmovable onits center, so that the head B is turned toan angleequahto thedistance between theI next iniet and outlet ports, the outlet-openings@become inlet'- ports, and vice versa.

In order to save space, the stear'n -inlet ports may be made annular andformed in the inner edge of the annular projection Dat each side, asshown'by the construction-lines atcin Fig. l. In the -bottom of thegrooves in the surface covered by the annular projection elongatedrecesses are then formed, which correspond to the recesses inthe annularprojection, which recesses communicate with the steam-chest. Moregrooves may be used-one outside of the other-which will then be coveredby a common cylinder-head, so that the pistons of one groove are placedin an intermediate position to those of the other grooves, the pressureon the cylinder-head varying less .from one to the other, so as to makean outer tightening between theV movable and stationy V1.- In arotary'steamengine, a cylinder hav:

v'ing anelliptical groove and a fixed cylinderhead having inlet andoutlet portsVn combination with the main shaft lhaving its bearing onthe cylinder, a cylinder-head attached to thesaid shaft and having anannular projection', pistons fulcrumed yon the said annular projectionand -operating in. the elliptical groove of the cylinder, and avalve-disk providedtwith ports, substantially as shown 'and described.

2. In a rotary steamfengine', a cylinder having an elliptical groove, incombination with a movable cylinder-head having an annular projection,and pistons fulcrumed on the said annular projection and traveling inthe elliptical groove of the cylinder, substantially as shownanddescribed. 3. In a rotary steam-engine, acylind'erhav ing an ellipticalgroove, afixed cylinder-head having inlet and outlet ports and forming asteam-chest between the cylinder and the cylinder-head, in combinationwith a movable cylinder-head having an annular projection, pistonsfulcrumed on the annular projection and traveling in the ellipticalgroove, and a valve-disk providedwithA ports and attached to the mainshaft, to which is secured' the movable cylinder-head, substantially asshown and described. l

In witness whereof I vhave'hereunto signed my name in the presence oftwo subscribing witnesses.

KARL AUGUST EKMAN.

Witnesses:

ALB. JUDERsoN, FRANS PETTERssoN.

